Microlens Array Homogenizer for Laser Illuminated Projector

Abstract

Laser light source is a potential illumination light source for non-emissive display applications, especially for liquid crystal projection displays, due to its requirement of low etendue source and highly polarized light. In order to make a conversion from a circular Gaussian beam profile to a rectangular uniform distribution, a microlens array has been proposed as a homogenizer. The analytical and experimental results show that the microlens array with a pitch of 100um under laser beam illumination works as a diffractive element, and a promising uniformity can be obtained with a stack of two microlens array.